2004 Legg Mason Tennis Classic
Date	August 16–22
Edition	35th
Category	International Series
Draw	32S / 16D
Prize money	$475,000
Surface	Hard / outdoor
Location	Washington, D.C., US
Venue	William H.G. FitzGerald Tennis Center
Champions
Singles
Lleyton Hewitt[1]
Doubles
Chris Haggard / Robbie Koenig[2]
← 2003 · Washington Open · 2005 →

The 2004 Legg Mason Tenis Classic was the 36th edition of this tennis tournament and was played on outdoor hard courts. The tournament was part of the International Series of the 2004 ATP Tour. It was held at the William H.G. FitzGerald Tennis Center in Washington, D.C. from August 16 through August 22, 2004.

Finals

Singles

Lleyton Hewitt defeated Gilles Müller, 6–3, 6–4

• It was Hewitt's 3rd title of the year and the 22nd of his career.

Doubles

Chris Haggard / Robbie Koenig defeated Travis Parrott / Dmitry Tursunov 7–6^(7–3), 6–1